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    <title>Document</title>
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<script>
    /*
    创建函数 生成当前时间的字符串
    2021-10-19 10:17:20
    作为函数的返回值返回
    */
   function identify(num){
       return num<10?"0"+num:num;
   }
    function createTimer(){
        var date1=new Date();
        var mi=date1.getMilliseconds();
        var year=date1.getFullYear();
        var month=date1.getMonth()+1;
        var day =date1.getDate();
        var hour =date1.getHours();
        var minute=date1.getMinutes();
        var sec=date1.getSeconds();
        month=identify(month);
        day=identify(day);
        hour=identify(hour);
        minute=identify(minute);
        sec=identify(sec);
        var result=year+"-"+month+"-"+day+" "+hour+":"+minute+":"+sec;
        return result;
   }
   document.write(createTimer());
   document.write((new Date).toLocaleString());
</script>
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